In the conventional approach to FM receivers typically one utilizes one separate electrical network for each function to be performed such as amplification, frequency mixing, demodulation, etc. In the present invention, FM receivers include one or a small number of electrical networks, such as two-terminal negative admittance networks which perform multiple functions to form complete receivers. The various functions performed simultaneously by the electrical networks are primarily based on particular features of the non-linear negative admittance of the two-terminal negative admittance network.
In another U.S. patent application Ser. No. 725,999 entitled "Two terminal negative admittance network" filed on Apr. 22, 1985 by the inventor of the present application, (now U.S. Pat. No. 4,625,186 issued Nov. 25, 1986) a pair of active elements such as transistors are employed in a novel circuit to form a negative admittance network. Although the disclosure of the above referenced application is incorporated in the disclosure of the present application, it is felt that the present invention would be more readily understood, if a brief description of the two-terminal negative admittance networks is included in this disclosure. The brief description will be found below.